Macaranga beccariana Merr., Webbia 7: 315 (1950)
Named after Odoardo Beccari [1843 - 1920] an Italian plant collector who collected extensively in the Malesian region.
Macaranga hypoleuca var. borneensis Hutch. ex Gibbs
Small trees up to ca. 20 m tall and 15 cm dbh, reproductive from 3 m tall and 3 cm dbh. Twigs hollow, ant inhabited, glabrous,
glaucous, with small ant openings (ca. 1 mm diameter). Stipules triangular, persistent, erect or spreading, 5-20 mm long by 3-7 mm wide.
Petioles glabrous, glaucous, up to 38 cm long. Leaves alternate, peltate, 3-lobed, 13-32 cm long by 10-30 cm wide, length/width-ratio
0.75-1.57; secondary veins 8-13, ending in the margin; central lobes 10-23 cm long by 3.8-9 cm wide, lateral lobes 9.5-22 cm long;
leaf base rounded, peltate margin length 2-4 cm; leaf margin with glands; leaf upper surface glabrous; leaf lower surface glabrous to
rarely hairy on veins, usually glaucous, not to sparsely gland dotted. Staminate inflorescences branched; flowers clustered per bracteole;
bracteoles with fimbriate margin. Pistillate inflorescences branched; fruits 5-6 mm wide, 3-locular, each carpel wall with glandular patch.
Tree, 15-17(-20) m tall, with simple architecture of the main trunk and secondary branches only;
twigs 7-8 mm in diam., glabrous, densely glaucous, bluish-green, hollow, housing ants. Bark smooth,
hoop-marked, often with stipule bases persistent, bluish-green even when mature, glaucous. Stipules
elliptic, 9-12 by 2.5-4.5 mm, coriaceous, spreading, not producing food-bodies, all pairs usually
persistent on the shoots after leaf fall. Leaves: petioles terete, slender, 10-30 cm long, shorter
towards shoot apex, glabrous, glaucous, strongly double pulvinate; blades ovate, 13-30 by 12-20 cm,
very deeply and narrowly trilobed, dissected almost to the petiole insertion or 4/5-7/8 of the leaf
length, leaf lobes elliptic, 2.5-4 cm wide, +/- equal in size, central lobe slightly constricted
near the base and becoming spathulate, lateral lobes slightly asymmetrical and ascending and curved
towards the slightly longer central lobe, 2-4 cm peltate, base rounded, margin entire, usually
slightly revolute, with small protruding, conical nectaries, apices finely acute to acuminate,
adaxial surface glabrous, abaxial surface sparsely villous with fine silvery hairs, densely
glaucous; 1st degree venation palmate with 8-10 prominent veins, 2nd degree venation strongly
looping and meeting the adjacent veins near the leaf margin, 3rd and 4th degree veins not or only
weakly scalariform; young leaves dark red-brown, scattered with long silvery hairs and ferrugineus
scaly hairs, producing food-bodies on lower surface. Staminate inflorescences particulate, erect,
7-20 by 5-10 cm, with minute ferrugineus hairs, 3 axis orders, main axis flattened, first pair of
secondary branches +/- opposite with accessory branches; bracts elliptic, c. 6 by 2.5 mm, margin
entire, apex acute, covered in minute ferrugineus scaly hairs, caducous; flower clusters with c.
10 flowers, decussately arranged and crowded on ultimate inflorescence branches; bracteoles ovate,
3-6 by 3-4 mm, enclosing the flower clusters, margin finely evenly pectinate with 10-16 teeth and
the apical one slightly elongated, apex acute, densely covered with minute ferrugineus hairs.
Staminate flowers c. 1 mm long, pedicellate; sepals fused, splitting to c. 1/4, apex densely
minutely ferrugineus hairy; stamens 1; anthers 4- (rarely 3-)locular. Pistillate inflorescences
narrowly paniculate, erect, 5-14 by 2-5 cm, slender, up to 2 axis orders, secondary branches +/-
opposite, covered in minute ferrugineus scaly hairs; bracts elliptic, c. 5-7 mm long, entire,
covered in ferrugineus hairs, caducous. Pistillate flowers c. 2-3 mm long, solitary in bracteole
axils; calyx urceolate, c. 1.5 mm long, minutely ferrugineus hairy, persistent; ovary 3-carpellate,
1-2 mm long; styles c. 1 mm long, free, spreading, persistent; stigma not dissected. Fruits
subglobose, 4.5-6 by 5-6 mm, pedicellate, glaucous, bluish green, two discrete glandular patches
on each carpel wall developing into slightly raised ridges, covered in bright yellow, sticky
exudate; pedicel 5-11 mm long, minutely ferrugineus hairy, strongly glaucous. Seeds +/- spheroidal
or slightly flattened, c. 3 mm in diam., black, with large shallow round pits and a small centrally
pointed linear scar, encased in a fleshy bright red aril. [from Flora Malesiana]
Collected up to ca. 850 m altitude. An early successional tree species, found on disturbed sites
in primary forest (gaps) and secondary forest. It appears to have a relatively wide tolerance of
soil conditions, occurring on heavily degraded sites as well as on more fertile sites. It is
uncommon in flooded or swampy areas.
Endemic for Borneo.